INVESTIGADORES
ASCOLANI Hugo Del Lujan
artículos
Título:
Adlayers of Alkanedithiols on Au(111): Effect of Disulfide Reducing Agent
Autor/es:
F. COMETTO; G. RUANO; H. ASCOLANI; G. ZAMPIERI
Revista:
LANGMUIR
Editorial:
AMER CHEMICAL SOC
Referencias:
Lugar: Washington; Año: 2013 vol. 29 p. 1400 - 1406
ISSN:
0743-7463
Resumen:
High-resolution photoemission spectroscopy is used to characterize
adlayers of ethane-, hexane-, and nonanedithiol molecules grown on
Au(111) surfaces by the immersion method. The effect of using a reducing
agent during and after the immersion to inhibit or eliminate SS bonds
is investigated. Our results demonstrate that immersion 24 h in
millimolar dithiol ethanolic solutions gives rise to the formation of
multilayers; this effect is more pronounced in the case of
ethanedithiol, the shortest molecule. A post-treatment with a disulfide
reducing agent is effective to produce monolayers of standing-up
molecules; this effect is again more pronounced in the case of
ethanedithiol. Finally, the immersion 24 h in a solution containing
dithiol and the reducing agent gives an unexpected result: most
molecules remain adsorbed in the lying-down configuration; in this case,
the almost complete suppression of the standing-up phase occurs equally
with the three types of molecules, which suggests that the formation of
SS bonds must be important for the lifting of the molecules.